Tri-printing squeegee moving mechanism of an automatic screen printing machine



Jan. 23, 1962 HISAKICHI ICHINOSE 3,017,824

TRI-PRINTING SQUEEGEE MOVING MECHANISM OF AN AUTOMATIC SCREEN PRINTING MACHINE 5 Sheets-Sheet 1 Filed Dec. 15, 1959 C [J HrsA KICHI IcHI/vm :3 INVENTORA 1 BY M MM VM ATMXWEKF 1962 HISAKICHI iCHINOSE 3,017,324

TRI-PRINTING SQUEEGEE MOVING MECHANISM OF AN AUTOMATIC SCREEN PRINTING MACHINE Filed Dec. 15, 1959 3 Sheets-Sheet 2 HISAKL'CHI ICHINOSE INVENTOR.

BY J

Jan. 23, 1962 FRI-PRINTING SQUEEGEE MOVING MECHANISM OF AN AUTOMATIC SCREEN PRINTING MACHINE Filed Dec. 15, 1959 5 Sheets-Sheet 3 H154 KZCHI l'cHrNosE INVENTOR.

Afro/W5 rs HISAKICHI ICHINOSE 3,017,824

United States Patent @fiicef ffiififi TIM-PRINTING SQUEEGEE MOVHNG MEQHANISM gF Ag AUTQMATEC SCREEN PRINTHNG MA- Hisakichi Ichinose, 175 Z-chome, Koushienguchi Hyogo Prefecture, Koushien, Nishinomiya @ity, Japan Filed Dec. 15, 1959, Ser. No. $59,609 Claims priority, application Japan May 26, 1959 3 Claims. (Cl. 101-123) The present invention relates to an improvement in a three squeegee printing means for an automatic screen printing machine of the type having a driving roller at one end of an endless belt and a follower roller at the other end, and means for intermittently driving the driving roller to intermittently move the belt between the rollers, and on which machine there are a plurality of printing frames in which the three squeegee printing means are installed'such that they can be reciprocated transversely of the direction in which the belt moves. During the operation of such a machine, the squeegees are reciprocated to print on the cloth on the belt by spreading ink thereover through a pattern in the screens mounted on the printing frames during the times that the belt is not moving between positions.

In the conventional three squeegee printing means, three printing squeegees are mounted on a single control shaft extending radially therefrom. When the control shaft is rotated slightly, one of the end squeeges is inclined sufliciently so that it is lifted from the surface of the screen on the printing frame, depending on which direction the control shaft is rotated. The control shaft is then moved horizontally and the ink is spread by the remaining two squeegees. At the end of transverse movement across the belt in one direction, the control shaft is rotated in the other direction, and the other end squeegee is lifted and the first end squeegee is returned onto the screen, and the control shaft then moves in the opposite transverse direction. However, with such a driving means, the ink may not be spread evenly because of the varied angles at which the squeegees are inclined to the screen surface. Moreover, the squeegee which has been lifted from the screen is at a rather sharp angle to the screen, and when the control shaft is moved with the raised squeegee leading, the leading squeegee is often pushed through the screen, and may form creases or otherwise damage the printing screen.

It is an object of the present invention to provide a three-squeegee printing means for an automatic screen printing machine which overcomes the drawbacks of the conventional means, and yet which is simpler in construction and which prints in an improved manner.

The printing means according to the present invention has three squeegees all suspended vertically with respect to the screen and transversely to the direction in which they are reciprocated. The mounting is such that the two outside squeegees are alternately raised and lowered, one being lowered when the other is raised, and the center squeegee being interlocked with the outside squeegees to be lowered with the one which is lowered. At the conclusion of the lowering movement, both the central and outside squeegee touch the screen with equal pres sure, and the position of the central squeegee is easily and precisely adjustable by means of a sliding wedge type of adjusting device.

Thus the squeegee printing means according to tht invention operates to spread the printing ink evenly and accurately due to the uniform angle of the two lowered squeegees and the even pressure which they exert on the screen, thus making possible printing special cloth and the use of special inks without unduly shortening the serviceable life of the screen or without deterioration of the finished printed cloth.

The invention will now be described with reference to the accompanying drawings, in which:

FIG. 1 is a partial side elevation view of the automatic screen printing machine with a multiple printing squeegee moving mechanism of this invention;

FIG. 2 is a side-view of the remaining part of the said automatic screen printing machine, the figures to be joined at line TT at the right end of FIG. 1 and line T--T at the left end of FIG. 2;

FIG. 3 is the plan view of FIG. 1;

FIG. 4 is the plan view of FIG. 2, FIGS. 3 and 4 to be joined at line UU at the right end of FIG. 3 and. line UU at the left end of FIG. 4;

FIG. 5 is a partial sectional elevational view, on an enlarged scale, showing the three printing squeegees and the carrying and moving mechanism therefor and the printing frame;

FIG. 6 is a sectional elevation view, on an enlarged scale, of the printing squeegee moving mechanism according to the invention;

FIG. 7 is a front elevation view of the mechanism of FIG. 6; and

FIG. 8 is a plan view of the mechanism of FIG. 6.

FIGS. 1 to 4 show the automatic screen printing machine to be equipped with this invention. Frame 1 ex tends the entire length of this machine, at one end of which is a driving roller 2 at the other end is a following roller 3. Between these rollers is stretched an endless belt 4 in such a way that the said belt 4 may be intermittently advanced in the direction shown by the arrow mark by intermittent revolutions of a driving roller 2. In this way, the following roller 3 is also revolved intermittently. On this endless belt 4, :a plurality of printing frames 5 are arranged (FIGS. 2 and 4 show 10 printing frames) and all of them are held by main frame 6. Extending in the transverse direction of the said main frame 6 are several guide rails 7 (FIGS. 2 and 4 show 6 guide rails), on which squeegee holders 8 are placed so as to be movable reciprocally in the transverse direction of printing frames at the required time. These squeegee holders can be joined to each other throughout the full length of the frame, or occasionally a few of them can be mounted to move independently of the others. From these squeegee holders, two or more squeegees are hung in each printing frame so as to come in contact with screens which are stretched across the bottom of each printing frame. Color paste is stored between the said squeegees to print cloth through the screen 56 when the squeegees slide on the screens. At the entry end of the frame 1, the feeding device 9 for cloth 12 to be printed is installed so that the cloth 12 is continuously fed from the entry to the exit, being agglutinated on the endless belt in accordance with the advances of endless belt. At the exit of the frame, the dryer 10 is installed for the after treatment of printed cloth as shown in FIGS. 1 and 3. The dryer 10 is equipped with a cloth discharge apparatus 11.

The moving mechanism for the three squeegees according to the present invention is illustrated in FIGS. 5-8. Movable beams 8a and 8b are provided for mounting the printing squeegees and are reciprocated horizontally from right end to left on printing frame 5 by a driving means not shown. On the bottom of the printing frame 5 is secured a screen 13. Printing squeegees 14, 15 and 16 are stopped at both ends of the printing frames in the positions shown in FIG. 6.

When the movable beams 8a and 8]) advance toward the right from the stopped position at the left end of printing frame 5, in the direction shown by arrow X in FIG. 5, movable beam 8a on the left, i.e. the trailing beam, descends and the carrying means for the central printing a squeegee is simultaneously lowered. The two squeegees are lowered suificiently so as to come in contact with the surface of the screen 13 with an even pressure. During the time that the lowered printing squeegees are sliding on the screen 13 toward the right, the color printing paste between squeegees is spread over the surface of the screen, thereby printing on the material beneath the screen. When the movable beams 8a and 8b advance to the left from the stopped position at the right end of printing frame 5, as shown by arrow mark Y, movable beam 8a ascends and movable beam 8b drops and simultaneously the support means for the central printing squeegee is lowered by the downward movement of movable beam 8b. Both printing squeegees consequently touch the surface of the screen 13 with equal pressure. As the said printing squeegees advance toward the left in this state, they spread the paste as in the movement to the right.

An axial groove 41 is provided in movable beam 8a, and a grooved collar 18 is firmly fixed to beam 8a so that it can not rotate and so that it is at an appropriate position along the axial length of movable beam 8a by means of upper set screw 17a which is engaged in said groove. Printing squeegee 14 is securely fitted on a bracket 19 by a lower lock nut 20a so as to be maintained in a perpendicular position relative to the screen 13. The upper part of this bracket 19 is attached to the said collar 18 by a middle set screw 21a, a ridge on bracket 19 fits into groove 22a in collar 18 in such a Way that bracket 19 is held in position. A lock nut 40a is provided on upper set screw 17a.

A construction is provided for movable beam 8b on the right of beam 8a. Grooved collar 24- is firmly fixed by upper set screw 17b so that it can not rotate, set screw 17!) being engaged in groove 23. To this collar, the upper part of bracket 25 is secured by means of middle set screw 21b, a ridge on bracket 25 fitting into groove 22b in collar 24 in such a way that the printing squeegee 15 attached to the said bracket in a position perpendicular to screen 13, the said printing squeegee being mounted on bracket'25 by lower lock nut 2012. Consequently, printing squeegee 14 moves up and down with movable beam 8a, and printing squeegee 15 moves with movable beam 8b. The descending and ascending motions are alternately achieved by a separate driving mechanism (not stown) for the beams.

A-central bracket 27 is slidably mounted on bracket 19 for movement in a direction perpendicular to screen 13. Leaf spring 26 mounted on the lower end of bracket 19 bears against central bracket 27 constantly urging it upwardly. On the lower part of bracket 27, is mounted printing squeegee 16, held to bracket 27 by means of lower lock nut 39. The upper end 28 of central bracket 27 is shaped in a form of the crown having upwardly facing inclined surfaces inclined in opposite directions. A threaded rod 31 for moving the central squeegee extends through a bore in bracket 19 and has a cross member on the end thereof with a downward facing inclined surface thereon engageable with one of the upwardly facing inclined faces on upper end 28 of central bracket 27. Whenthe inclined plane 29 on the said cross member contacts the left-hand inclined surface at upper end 28 of central bracket 27, the upward movement of central bracket 27 and central printing squeegee 16 is limited to such 'a degree that parts 27 and 16 cannot be raised beyond the point of engagement. There is also provided an inclined surface 30 on a cross member on threaded rod 32 extending through bracket 25 for adjusting the central squeegee from the opposite side when inclined surface 3 comes in contact with right-hand inclined surface at the upper end 28 of the central bracket 27.

The adjustment of the vertical position of central printing squeegee 16 relative to the surface of screen, which is one of the features of the present invention, is easily and accurately carried out by engagement of the inclined surfaces of the top of central bracket 27 and 4 surfaces 29 and 30 on the ends of rods 31 and 32. Both rods 31 and 32 can be moved horizontally by tightening and loosening central squeegee adjusting nuts 33a, 33b, central printing squeegee 16 thereby being vertically raised and lowered by the contact of the inclined surfaces 29 and 30 with the inclined surfaces at the upper end 23 of central bracket 27.

The adjustment of the elevation of printing Squeegees 14 and 15 relative to screen 13 may be accomplished by turning adjusting nuts 35a and 35b inside holders 34a and 34b for the squeegee adjusting screw, which holders are mounted on brackets 19 and 25, lower lock nuts 20a and 20]) being temporarily loosened during the adjustment. Adjusting screws 36a and 36b interlocked with adjusting units 35a and 35b are thereby raised or lowered. Since each adjusting screw 36a and 36b is coupled with squeegee holder plates 37a, 37b by pins 38a, 38b, printing squeegees 14 and 15 are raised or lowered during the ascent or descent of adjusting screws 36a and 36b. It is necessary to tighten lower lock nuts 20a and 20b after adjusting the elevation of printing Squeegees 14 and 15.

In operation, when the movable beams 8a and 8b advance toward the right in the direction of arrow X in FIG. 5, movable beam 811 on the left descends. Printing squeegee 14, fixed on bracket 19 and rod 31 for adjusting central squeegee are also lowered because these parts are fixed to the said movable beam 8a. As bracket 19 descends, central bracket 27 and printing squeegee 16 are pressed down, because the inclined surface 29 on the cross member on the end of rod 31 presses down on the left inclined surface of the bracket 27. In this way, printing squeegees 14 and 16 spread the color paste poured at intervals between printing squeegees 14, 16 and 15 over the surface of screen 13, the color paste passing through the pattern in the screen 13 to cloth or the like under the screen 13. Printing is thus accurately carried out. During this motion, movable beam 8b on the right, bracket 25, printing squeegee 15, and rod 32 are raised and the inclined surface 30 on the cross member on rod 32 is spaced from the right inclined surface of central bracket 27. When the movable beams 8a and 8b subsequently advance to the left in the direction of arrow Y in FIG. 5, movable beam 3b on the right is lowered. Consequently, printing squeegee 15, bracket 25 and rod 32 are also lowered. As the said rod 32 for adjusting the central squeege descends, the inclined surface on the right side of upper end 28 of central bracket 27 is engaged by the inclined surface 30 on the cross member on the end of rod 31 for adjusting the central squeegee. As a result, the right end of spring 26 fixed to the lower end of bracket 19 is pressed down. Consequently, central bracket 27 and printing squeegee 16 are pressed down at the same time as printing squeegee 15. Printing squeeges 16 and 15 lowered in this way spread the color paste poured between squeeges 14, 16 and 15 over the surface of screen 13, the spread paste passing through the pattern of the said screen to print the cloth on return stroke. During the reversal of the squeegees, however, the cloth 12 has been moved forward one pitch by a separate driving arrangement.

In this fashion, central printing squeegee 16 is constantly pushed down to the surface of screen 13 either by rods 31 or 32 for adjusting the central squeegee while the movable beam 8a and 8b are reciprocated horizontally. Consequently, printing may be performed twice in one stroke, always being performed by two printing Squeegees. Accordingly, the printing time may satisfactorily be cut down to /2 that required for printing by the use of the conventional dual-printing squeegee mechanisms where printing is carried out in two strokes by either of two squeegees alternately descending and ascending. Furthermore, because the printing squeeges do not slide over one section of pattern twice during the reciprocating motion, the screen is held firm and overlapped printing is thus prevented by the use of the three printing squeegee moving mechanism in accordance with the present invention.

Moreover, at both ends of the reciprocating strokes, the two movable beams 8a and 8b for setting printing Squeegees may be suspended horizontally at such an elevation by the separate driving mechanism, as shown in FIG. 6, that the printing squeegees attached to the said movable beams may be made to contact the surface of the screen lightly without causing any damage to the said surface. The adjustment of the central printing squeegee may easily and accurately be carried out by the use of the adjusting screw threaded rods, and yet the device of the present invention permits easy washing and handling of the printing squeegees in comparison with other conventional printing squeegee moving mechanism.

It is thought that the invention and its advantages will be understood from the foregoing description and it is apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing its material advantages, the form hereinbefore described and illustrated in the drawings being merely a preferred embodiment thereof.

What I claim is:

1. In a screen printing machine having a screen with apertures therein in the pattern to be printed, the combination of a first beam and a second beam movable back and forth along said screen with the leading beam in a position higher than the trailing beam, an end squeegee fixedly mounted on said first beam and an end squeegee fixedly mounted on said second beam, said squeegees being fixed in a position perpendicular to said screen, a central squeegee mounted on one of said beams perpendicular to said screen and movable perpendicularly to said screen,

and adjusting means associated with each end squeegee and engageable with the top of said central squeegee for adjusting said central squeegee vertically, the adjusting means associated with the end squeegee on the other of said beams engaging said central squeegee and moving it to the lower position when said one of said beams is in the upper position, whereby said central squeege is always in the lower position when the beams move back and forth along the screen.

2. The combination as claimed in claim 1 in which said end equeegees are mounted on said beams by means of a bracket engaging the beam on which the end squeegee is mounted, said central squeegee being mounted on one of the brackets, and said adjusting means comprising a threaded rod extending through the bracket and having a cross member on the end thereof engageable with the top of said central squeegee.

-3. The combination as claimed in claim 2 in which the top of said central squeegee has upwardly and outwardly facing inclined surfaces thereof, and each cross member has a downwardly facing inclined surface complementary to an inclined surface on the central squeegee.

References Cited in the file of this patent UNITED STATES PATENTS 2,209,688 Davis July 30, 1940 2,265,266 Cote Dec. 9, 1941 2,529,250 'Fordyce Nov. 7, 1950 2,775,780 Pisano Jan. 1, 1957 2,793,586 Arelt May 28, 1957 2,863,382 Giani Dec. 9, 1958 FOREIGN PATENTS 426,833 Great Britain Apr. 10, 1935 

